Longest phase of oestrus cycle

Longest phase of oestrus cycle Diestrus.
This phase is characterized by the activity of the corpus luteum, which produces progesterone. The signs of estrogen stimulation subside and the corpus luteum starts to form. The uterine lining begins to appear.
The vaginal cytology during metestrus consists of many leukocytes along with nucleated cells and cornified cells. Diestrus is the longest phase, lasting roughly 57 h, and the vaginal smear consists primarily of leukocytes. Estrus detection in vaginal smears.